Condenser assembly



June 25, 1940. H. HARTZELL 2,205,816

CONDENSER ASSEMBLY Filed Nov. 15, 1957 INVENTOR HEEMA/V L. fieTZELL ATTORN EYS Patented June 25, 1940 UNITED STATES PATENT OFFICE CONDENSER ASSEMBLY Herman L. Hartzell, Anderson, 1nd,, assignor to General Motors Corporation, Detroit, Micln, a corporation of Delaware Application November 15, 1937, Serial No. 174,521

7 Claims. (Cl. 175-41) This invention relates to condensers and more Fig. 5 is a sectional view taken on the line 6-5 particularly to that type of condenser used of Fig. 4. for ignition apparatus for internal combustion Fig. 6 is a wiring diagram showing the elements engines. of the condenser assembly, shown in Fig. 1, illus- It has been discovered that the capacity of trating their relative position and circuit con- 5 the condenser decreases with lower temperatures nections within the ignition system. and the amount of decrease depends upon the v Fig. 1 is a wiring diagram showing the elements type of materials used in the condenser. In the of the condenser assembly, shown in Fig. 4, toconstruction of condensers used with ignition gether with an additional condenser illustrating apparatus, the capacity will decrease approxitheir relative positions and circuit connections mately percent when the temperature is lowwithin the ignition system. ered from 25 C. to 25 C. The result is that With particular reference to Figs. 1, 2, and 3, there is a lower capacity across the ignition condesignates a tubular metallic can or casing tacts during cold weather than there is during having a closed end 2i, which is provided with 15 normal or hot weather. However, during cold an opening 22. The casing 23 encloses a con- 15 weather with the lower coil resistance and higher denser assembly 25, and a thermostatic switch battery voltage, the primary current is much assembly 26. higher than it is during warm weather so that The preferred form of the condenser assembly a larger capacity is required if satisfactory point 25, shown in Fig. 1 comprises a condenser unit 20 operation is to be obtained. 33 wound into cylindrical form and separator 32 20 An object of the present invention is to proof insulating material. In the form disclosed in vide a condenser assembly which will provide Fig. l the condenser units are. formed by first extra capacity at low temperatures. This is acwinding insulating strips 34 and 35 of foil upon complished by producing a condenser and thera tubular core 36 of insulating material. The mostatv arrangement in which the thermostat strips of foil 34 and 35 are separated by layers 23 operates to connect an additional condenser unit of insulating paper 31. After the condenser unit in parallel with the main ignition condenser unit has been wound into cylindrical form to the at low temperatures. This arrangement will desired capacity several turns of insulating paper, allow the use of higher average primary current namely the insulator 32, is wound about the unit 60 without having excessive contact burning during 33 to provide a physical separation between the 30 cold weather. If the additional capacity were condenser units 33 and 3|. Upon completion of connected permanently in the circuit, excessive the winding of t e Sep t Condenser unit contact pitting would be the result during warm 3|, comprising insulated foils 31a and a, is weather, thus the thermostat operates to diswound upon the condenser assembly 30 until the 35 connect the condenser from the circuit accordcondenser assembly 3| is completed to the de- 86 ing to temperature conditions. sired capacity. 'It will be noted that the foil Another object of the present invention is to margins 34 and 340 project beyond the margins provide a condenser and thermostat assembly of the insulation 36 at the thermostat end of enclosed within a single case. the condenser, and the foil margins 35 and 35a 40 Further objects and advantages of the present P oject beyond the insulation at the terminal 40 invention will be apparent from the following end of condenser. description, reference being had to the accom- As is well known to makers of this type of panying drawing wherein a preferred embodicondenser, the side margins of foil strips may ment of the present invention is clearly shown, be readily crushed together to form a mass of In the drawing: foil metal at each endof the condenser units to 45 Fig. 1 is a longitudinal sectional view, on an pr v m nsfor hin e or r conenlarged scale, of a form of condenser embodyu t the f In the form Shown in F 8- [III ing the present invention. a conductor cable 40 having a bared end ll Fig. 2 is a perspective view of several of th is soldered to the crushed foil ends 35 and 35a parts of the thermostat, inseparated relation, of the units 30 and 3L 50 I before assembly. Associated with the condenser units 30 and 3| Fig. 3 is a perspective view of additional parts is the thermostatic switch device 26. The switch of the thermostat before assembly. itself comprises a base 53 of insulating material,

Fig, 4 is a modified form of the present invenand as shown the outer face 5| of the support, tion taken on line 4 -4 of Fig. 5. see Fig. 2, is provided with a plurality of bosses 55 denser 3 I or projections 52 and a recess while the oppo= site or inner face 54 of the support, see Fig. 3 is provided with a raised portion 55 of non-circular contour. An internally threaded insert 56 is embedded in the support and is provided with a flange 5'! which extends beyond the inner face 54 of the support 50. Supported on the inner face 54 of the support is a cup-shaped member 58. This member is provided with a non-circular opening 59 to receive the projection or raised portion 55 which projection operates to prevent the cup-shaped member from turning relative to the support. The cup-shaped member is also provided with an apertured ear 60. As illustrated in Fig. 3, it is preferred that the ear be formed integral with the member 56 and this is accomplished by stamping-the ear 65 from the side wall of the member 58. In order to maintain the cup-shaped member to the support the apertured ear is fitted over the flange portion 57 of the insert 56 which is spun over the ear. An insulating disc 6! and a ground strap 62 are secured on the raised portion and within the cupportion of the member 58 by rivets 65. These rivets also secure a bi-metallic member 64 and a U-shaped ground strap 65, which straddles the bi-member 64, to the outer face of the support. The yoke portion of the strap 65 is deformed as at 66 and adapted to extend into the opening 2! and contact the casing 26.

The free end of the bi-metallic member 55 carries a movable contact 61! and said member is so constructed that it normally maintains the contact 6! out of engagement with a relative stationary contact 66 during normal or hot temperatures. The relative stationary contact has screw threaded engagement with the insert 56 so that it may be adjusted to suit the various climatic sections to which it is subjected.

In assembling the thermostatic switch device 26 and condenser assembly 25, the thermostatic switch device 26 is first placed into the case so that the detent 66 of the ground strap 65 will extend into the opening 22 in the bottom wall 2!. Then the condenser assembly comprising the units and 3i, is placed therein. It will be noted that the end of the separator 32 adjacent the thermostatic switch device 26 extends beyond the margins of foil 34 and the round strap 62 and bears against the insulating disc 60 so as to insulate the margins 34a of con- The conductor 40 is threaded through suitable apertures of an insulating disc 10, a resilient metal washer ii, and through a neck portion I2 of a cover I3. The cover is also provided with a peripheral flange which fits snugly within the interior of the case 20. The

cover is forced toward the condenser form with substantial pressure sufficient to cause the margins 34!) of foil 34 to bear against the strap 62, the foil margins 351) against a peripheral flange I5 provided by the cup-shaped member 58 and the detent 66 against the bottom V2! to form good electrical'connections between the" the cover in position and the condenser margins 34!) and b firmly against the strap 62 and flange 15, respectively, and prevent endwise movement of the elements within the case.

neck portion i2 is deformed as at T! to grip the insulation of the conductor and provide a moisture seal between the cover and the cable. The aperture M is filled with solder 18 so to form a seal for the bottom 2! and also assists in maintaining a good ground connection between the ground member 65 and the case 20.

In the modified form of the present invention, shown in Figs. 4 and 5, the casing I20 is adapted to receive a thermostatic switch device I26 and a condenser body E25. In this instance the condenser body I25 is wound into cylindrical form by winding insulated strips I 34 and I35 of foil upon a tubular core 836. The layers of foil are separated by insulating paper I3! with the foil margins I340: and I35a respectively extending beyond opposite side margins of the paper 36.

The thermostatic device I26 comprises a support H40 with a leg I. The leg is deformed to provide a projection I42 which is adapted to fit into the aperture I25 of the case i20. An car I43 formed integral with the leg I4! and is bent at an angle and supports an adjustable contact Mil. A bi-metallic member I45 and an L-shaped bracket M6 are insulatingly supported upon the support M0, as clearly shown in Fig. 5, but the bi-metallic member [I45 and the bracket I46 are electrically connected to each other.

A conductor I156 having a bared end is soldered to the margins of foil 635 as indicated at I152. The bracket I146 comprises leg portions I153 and (I54. The leg portion II53 is formed so as to sumI port one end of the condenser body I25.

A strap or connector I55 preferably has one end thereof soldered to the leg portion 054 and the other end is soldered to the margins of foil 1134. A movable contact I56 is carried by the free end of the bi-metallic member I45. This contact is normally separated from the relative stationary contact by the bi-metallic member I45 during warm weather, but the member I45 is adapted to fiex upwardly, as viewed from Fig. 4, from its normal position in cold weather so that the movable contact I56 will engage the contact I44 to ground the foil I34 through elements I55, I46, I45, I56, I44, I40 and 20.

In assembling the condenser, shown in Fig. 4 and Fig. 5, the thermostatic switch I26 is so positioned that the projection I42 will extend into the aperture I2! and in contact with the casing I20. Then the cable I50 is threaded through an aperture of an insulated disc I60 and through a hollow boss provided by cover I6I, after which the cover is foced into the case 20 with substantial pressure sufilcient to cause the margins I340. of foil I34 to be crushed against the strap connector I55 and the leg I54 to provide a good electrical connection for the foil I34. While this pressure is applied to the condenser cover I6! the end margin I62 of the case is spun over the cover to retain the cover in position and prevent the thermostatic switch and con.- denser assemblies against longitudinal movements within the case.

Referring to .Fig. 6. the dash' line 20 represents. the casing of the condenser assembly 25 shown in Fig. 1. The casing operates as a conductor or terminal for the condenser units 30 and 3! to represents the casing of the condenser assembly shown in Fig. 4 while dash lines 250 represents a second condenser employed in the ignition system.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of th claims which follow. 7

What is claimed is as follows:

1. A condenser assembly for an ignition system comprising in combination; a metallic case; a condenser body comprising foils and insulating strips; a conductor electrically connected to one of the foils; a support provided with a fixed contact; means for connecting the other foil with the fixed contact; a thermostatic strip anchored to the support and arranged to flex in response to temperature changes; a contact carried by the free end of the strip and normally held out of engagement with the fixed contact; and means,

for connecting the strip with the case so that the second mentioned foil will be grounded upon closure of the contacts.

2. In a condenser assembly for an ignition system the combination comprising; a metallic case; a condenser body including windings of foils and insulating strips, the side margins of the foils projecting respectively beyond the side margins of the insulating strips; a conductor connected to one of the foil margins; a base provided with a stationary contact; means for connecting the other foil margin with the stationary contact; a thermostatic strip anchored to the base .and capable of bending in response to low temperatures; a contact carried by the free end of the strip and normally held out of engagement with the stationary contact; and means for connecting the strip with the case for grounding the second mentioned foil margins upon closure of the contacts.

3. In a condenser assembly for an ignition system the combination comprising; a metallic case; a condenser body including windings of foils and insulating strips, the side margins of the foils projecting respectively beyond the side mar- .gins of the insulating strips; a conductor con- 4. A condenser assembly for an ignition systemcomprising in combination; a metallic case having a closed end; a condenser body comprising windings of foils and insulating strips the side margins of the foils projecting beyond the side margins of the insulating strips; a conductor connected to one of the foil margins; a base supporting a normally stationary contact; a plate associated with the stationary contact and connected with the other foil; a movable contact; a thermostatic element carrying the movable contact and normally holding same spaced from the stationary contact and capable of bending at low temperature to close the contacts; and a grounding strap connecting the thermostatic element with the closed end of the case whereby the second mentioned foil will be grounded upon closure of the contacts.

5. A condenser assembly comprising in combination; a tubular metallic casing having a closed end; a condenser foil assembly including a body of windings of foils and insulating strips, the

,side margins of the foils projecting respective 'ly beyond the side margins of the insulating strips; a conductor electrically connected to one of'the foils; a support; an adjustable contact carried by the support; a thermostatic element and a grounding member secured together at one of their ends to the support, a movable contact carried by the thermostat and normally out of engagement with the stationary contact, but said element capable of bending at low temperature to close the contacts so as to ground the other foil, a cover for the open end of the casing and having 'an aperture through which the conductor passes; and means for securing the cover and for clamping the second mentioned foil margins against the adjustable contact and for urging the other end of ground member against the closed end of the case.

6. A condenser assembly for an ignition system comprising, in combination; a metallic case; a condenser body comprising separate units of foils and insulating strips; supported within the case; a conductor electrically connected to one of the foils of each unit; means for connecting the other foil of one unit with the case; normally separated contacts located within the case one other foil of the second unit with one of the contacts; and a bi-metallic member for connecting the other contact with the case, said bi-metallic member operable at a low temperature to close the contacts whereby the other foil of the second mentioned unit is grounded to the case.

7. A condenser assembly comprising in combination; a condenser body comprising separate units of foils and insulating strips; a conductor electrically connected to one foil of each unit;-

means for connecting positively the other foil of one unit to ground; a stationary contact; a thermo responsive contact; means for connecting one of the contacts to ground; and means for connecting the other contact withvthe other toll of the second unit.

HERMAN L. HAR'IZELL.

of which is movable; means for connecting the 

